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In augmented reality, it is important to achieve visual consistency between inserted virtual objects and the real scene. As specular and transparent objects can produce caustics, which affect the appearance of inserted virtual objects, we herein propose a framework for differential rendering beyond the Lambertian-world assumption. Our key idea is to jointly optimize illumination and parameters of specular and transparent objects. To estimate the parameters of transparent objects efficiently, the psychophysical scaling method is introduced while considering visual characteristics of the human eye to obtain the step size for estimating the refractive index. We verify our technique on multiple real scenes, and the experimental results show that the fusion effects are visually consistent.

We have investigated the structure of the Hercules supercluster (SCL160) based on data originally extracted from the Sloan Digital Sky Survey SDSS-DR7. We have traced the mass distribution in the field through the numerical density-weighted by the $r^\prime$-luminosity of the galaxies and classified them based on their spatial position and redshift. This has allowed us not only to address the kinematics of the supercluster as a whole, but also the internal kinematic of each cluster, which was no further explored before. We have confirmed that the Hercules supercluster is composed of the galaxy clusters A2147, A2151, and A2152. A2151 consists of five subclusters, A2147 on two and A2152 on at least two. They form the heart of the Hercules supercluster. We also have found two other gravitationally bond clusters, increasing, therefore, the known members of the supercluster. We have estimated a total mass of $2.1\pm0.2 \times 10^{15}$ M$_\odot$ for the Hercules supercluster. To determine the dynamical masses in this work, we have resorted to the $M_{200}-\sigma$ scaling relation and the caustic technique. Comparing both methods with simulated data of bimodal merging clusters, we found the caustic, as well as the $\sigma$-based masses, are biased through the merger age, showing a boost just after the pericentric passage. This is not in line with the principle of the caustic method that affirms it is not depending on the cluster dynamical state., Comment: 20 pages, 11 figures, 7 tables - Accepted for publication in MNRAS

The optimal technological parameters for the production of caustic soda from sodium carbonate and sulfate and calcium hydroxide have been established. The influence of the concentration of lime milk on the rate of filtration by sediment and filtrate has been studied. Purpose of the Work: The purpose of this work is to determine the physicochemical basis for the production of sodium hydroxide and burkeite by causticization of sodium carbonate and sulfate. Scientific Novelty: In comparison with the known works, a theoretical profoanalytical analysis of the one-cation of four-component system and its constituents was carried out for the first time, and also determined the optimal technological parameters of causticization of solutions for local carbonates and sodium sulfates. Features of the Work: - the influence of the main technological parameters on the processes of causticization, filtration, evaporation; - research of intermediate and finished products by modern physicochemical methods; - study of the rheological properties of the solution depending on the temperature and concentration of the resulting solutions.

One possibility for detecting low-amplitude pulsational variations is through gravitational microlensing. During a microlensing event, the temporary brightness increase leads to improvement in the signal-to-noise ratio, and thereby better detectability of pulsational signatures in light curves. We explore this possibility under two primary considerations. The first is when the standard point-source and point-lens approximation applies. In this scenario, dividing the observed light curve by the best-fitted microlensing model leads to residuals that result in pulsational features with improved uncertainties. The second is for transit events (single lens) or caustic crossing (binary lens). The point-source approximation breaks down, and residuals relative to a simple best-fitted microlensing model display more complex behavior. We employ a Monte-Carlo simulation of microlensing of pulsating variables toward the Galactic bulge for the surveys of OGLE and of KMTNet. We demonstrate that the efficiency for detecting pulsational signatures with intrinsic amplitudes of $350$, is $\sim 50-60\%$. The maximum efficiency occurs for pulsational periods $P \simeq 0.1-0.3$ days. We also study the possibility that high-magnification microlensing events of non-radially pulsating stars (NRPs) could be misinterpreted as planetary or binary microlensing events. We conclude that small asymmetric features around lightcurve peaks due to stellar pulsations could be misdiagnosed with crossing (or passing close to) small caustic curves., Comment: 11 pages, 4 Figures, 4 Tables

We present an analysis of the intracluster light in the Frontier Field Cluster MACS J1149.5+2223 (z=0.544), which combines new and archival Hubble WFC3/IR imaging to provide continuous radial coverage out to 2.8 Mpc from the brightest cluster galaxy. Employing careful treatment of potential systematic biases and using data at the largest radii to determine the background sky level, we reconstruct the surface brightness profile out to a radius of 2 Mpc. This radius is the largest to which the intracluster light (ICL) has been measured for an individual cluster. Within this radius, we measure a total luminosity of 1.5e13 Lsun for the brightest cluster galaxy plus ICL light. From the profile and its logarithmic slope, we identify the transition from the brightest cluster galaxy to ICL at r~70 kpc. Remarkably, we also detect an inflection in the profile centered in the 1.2-1.7 Mpc (0.37-0.52 r200m) radial bin, a signature of an infall caustic in the stellar distribution. Based upon the shape and strength of the feature, we interpret it as potentially being at the splashback radius, although the radius is smaller than theoretical predictions. If this is the splashback radius, then it is the first such detection in the ICL and the first detection of the splashback radius for an individual cluster. Similar analyses should be possible with the other Frontier Field clusters, and eventually with clusters from the Euclid and Roman missions., 8 pages, 5 figures, submission to MNRAS

Achieving interactivity for applications with physically-accurate caustics is proven to be a challenging task. We present a hybrid method utilizing ray tracing and rasterization which enables water caustic coverage to vast view distance in real-time. Inspired by photon mapping, we optimize the generation of photons using cascaded caustic maps to avoid tracing the first bounce of a ray from a light, replacing that step with rasterization. We introduce cascades as a set of caustic maps with varying resolution based on the distance from the viewer. In addition, since we adopt a splatting approach where each photon is rasterized into the image based on the extent of its contribution, we trace photon differentials in order to determine the size, shape and intensity of the splats so as to achieve adaptive anisotropic flux density estimation. Finally, to mitigate undersampled regions where lack of photons leads to noise, we propose the use of a cross-bilateral filter with an adaptive kernel radius. The radius is based on the perceived radiant energy of a photon relative to the scene’s luminance, and drastically improves performance. We demonstrate how the use of our method is able to perform interactive rendering of large-scale dynamic water caustics.

One of the advantages of observations of gravitational microlensing is stellar spots detection. Our aim ‎in this paper is to study and characterize the perturbations due to stellar spots on the microlensing ‎light curves. Considering a suitable formalism for the stellar spots, we simulate the microlensing of ‎spotted source stars. One of the effects of a spot on stellar light curve is the local demagnification (where ‎the lens is crossing the stellar spot) and it causes asymmetric perturbations on the light curve. The ‎spots that locate at the source center after projection make larger and deeper perturbations than the ‎spots locate the stellar limbs. In caustic crossing binary microlensing events, the typical-size spot-‎induced perturbations mostly make (more than 40‏‎ percent) the relative deviations larger than ‎‏5‏‎. This ‎fraction is bigger for single lensing events‎‎‎.‎

The effectiveness of multiple cleaning in place (CIP) procedures was observed from different local breweries in the North East of England. Experiments were also carried out to investigate possible reductions in chemical, water and energy use with regards to CIP, without compromising the effectiveness of the CIP performed. The effectiveness of CIP cycles was quantified using Hygiena’s UltraSnap adenosine triphosphate (ATP) swabs, with a relative light unit (RLU) tolerance of

This work is devoted to the study of photon mapping methods applied to realistic rendering. In distinction from the conventional rendering methods, the calculation of the indirect and caustic luminance is based on backward photon maps (which are also called observation maps). The main advantages of this method are described. These advantages are the natural distribution of the photons in the regions forming the image luminance and the reduction of the number of photons formed on the trace of one ray. The main algorithmic difficulty of the backward photon mapping method is discussed, which is the necessity to synchronize data access during the calculations and accumulate the luminance due to indirect and caustic illuminance. To resolve this difficulty, it is proposed to use intermediate photon maps of the indirect and caustic illumination distributed over the computation threads that render the corresponding parts of the image. Based on this analysis, the method of progressive backward photon mapping is introduced, and an algorithm of realistic rendering based on this method is described. The proposed algorithm does not require additional synchronization during the accumulation of luminance at the image points, which makes it possible to efficiently implement it not only on the central processor but also on graphics processors (GPUs). Results of the qualitative and quantitative comparison of the rendering results produced by the methods of progressive forward and backward photon mapping are presented.

Изготовление оборудования для упаривания щелочи натрия на сегодняшний момент требует ответственного подхода к выбору материалов, поскольку повышенная агресивность концентированных растворов вызывает некоторые сложности во время произвоства. В статье рассмотрена коррозионная стойкость отечественных и зарубежных материалов, как основного металла, так и сварных соединений в средах концентрирования электролитических щелоков в интервале концентраций NaOH от 12% до 99.5% и температуры от 115 до 395оС. Для испытаний из исследуемого материала изготавливались образцы размером 20×80 мм с поперечным сварным швами с двумя просверленными отверстиями. шлифовались и собирались в кассеты с помощью стержней из никелевого сплава. Впервые получены сравнительные данные по коррозионному состоянию конструкционных материалов при упаривании электролитических щелоков, полученных диафрагменным электролизом и электролизом с использованием ртутного катода. Результаты коррозионных исследований достаточно хорошо корректируются с опытом эксплуатации никелевых труб на первой стадии концентрирования щелочи. Оценена электрохимическая гетерогенность сварных соединений сплавов 33 и 201, изготовляемых фирмой «Крупп ВДМ». Проведенные исследования коррозионной стойкости сплавов 201 и 33 в условиях упаривания NaOH, полученного ртутным электролизом, подтвердили высокую коррозионную стойкость никелевого сплава 201 на основных стадиях концентрирования щелочи. Результаты исследования могут использоваться в качестве рекомендаций при разработке конструкционных материалов. The manufacture of equipment for the evaporation of sodium alkali at the moment requires a responsible approach to the choice of materials, since the increased aggressiveness of concentrated solutions causes some difficulties during production. The article considers the corrosion resistance of domestic and foreign materials, both the base metal and welded joints in the media of concentration of electrolytic alkalis in the range of NaOH concentrations from 12% to 99.5% and temperatures from 115 to 395оС. For testing, specimens of 20×80 mm in size with transverse welds with two drilled holes were made from the material under study. polished and assembled into cassettes using nickel alloy rods. For the first time, comparative data on the corrosion state of structural materials during evaporation of electrolytic slits obtained by diaphragm electrolysis and electrolysis using a mercury cathode were obtained. The results of corrosion studies are quite well corrected with the experience of operating nickel pipes at the first stage of alkali concentration. The electrochemical heterogeneity of welded joints of alloys 33 and 201 manufactured by “Krupp VDM” was evaluated. The conducted studies of the corrosion resistance of alloys 201 and 33 under conditions of evaporation of NaOH obtained by mercury electrolysis confirmed the high corrosion resistance of nickel alloy 201 at the main stages of alkali concentration. The research results can be used as recommendations for the development of structural materials.

A Response Surface Methodology was applied as predictive tool for biodiesel optimisation from remediated Waste Cooking Oil (WCO). Caustic potash was synthesised from plantain peels and used for WCO...

We prove that the manifold of non-singular points of a stable real caustic germ of type and the manifolds of points of transversal intersection of its smooth branches consist only of contractible connected components. We also calculate the number of these components.

We present an algorithm for designing and manipulating pulsed caustic (accelerating) beams that propagate along a predefined planar curved beam-axis trajectory in free space. These pulsed beams are localized time-dependent wave packets. We evaluate the pulsed aperture field (source) distribution that radiates the beam along the desired trajectory. The aperture field is evaluated by setting its delay to form the caustic surface about the beam-axis skeleton and to control the lateral beamwidth, and the amplitude is chosen to form a uniform intensity profile of the beam along its axis. Numerical examples are included.

Self-accelerating beams have the unusual ability to remain diffraction-free while undergo the transverse shift during the free-space propagation. We theoretically identify that the transverse optical field distribution of 2D self-accelerating beam is determined by the selection of the transverse Cartesian coordinates, when the caustic method is utilized for its trajectory design. Based on the coordinate-rotation method, we experimentally demonstrate a scheme to flexibly manipulate the rotation of transverse optical field for 2D self-accelerating beams under the condition of a designated trajectory. With this scheme, the transverse optical field can be rotated within a range of 90 degrees, especially when the trajectory of 2D self-accelerating beams needs to be maintained for free-space photonic interconnection.

Carbon dioxide (CO2) is one of the corrosive element which exists in oil and gas industries. To prevent CO2 corrosion on carbon steel pipelines, amine-base solvent and caustic solutions are commonly applied. Accordingly, effectiveness of amine base solvent and caustic solutions to reduce risk of corrosion becomes key parameters in determining service lifetime of pipelines made of carbon steel. In this research, the corrosion rate of carbon steel A106 Gr B in amine solutions combined with saturated CO2 gas and caustic solution was studied. The experiments were carried out in static conditions and the Linear Polarization Resistance (LPR) technique was used to measure the corrosion rate (as per ASTM G 5-94). It was found that the corrosion rate in the amine-based solution had shown remarkable results. Somehow, the corrosion rate in an amine-based solvent containing saturated CO2 gas has increased to 200%. The temperature increment to 50°C from room temperature has also increased the corrosion rate. Meanwhile, the caustic addition in amine solution has reduced the corrosion rate of carbon steel.

Three approaches were examined for the reutilization of cold caustic extraction (CCE) lye. The term CCE lye refers here to the used NaOH solution with relatively high alkali content, which could be wasted if not reused properly. The results showed that CCE lye can be effectively applied in deinking, alkaline hydrogen peroxide bleaching, and oxygen delignification processes. The CCE lye improved the physical strength of the dried sheet of pulp, as the tensile index increased by 17.9% to 40.5%, the tear index increased by 2.9% to 22.2%, and the burst index increased by 10.5% to 41.0%. The results demonstrated the feasibility of integrating the CCE process of dissolving pulp production with regular pulping and bleaching processes.

Porous silica is a well-established material for industrial-scale chromatographic separations and as catalyst supports because of its precisely defined and open pore structure. The Achilles heel of...

The article considers the corrosion resistance of domestic and foreign materials, both the base metal and welded joints in the media of concentration of electrolytic alkalis in the range of NaOH concentrations from 12% to 99.5% and temperatures from 115 to 395°С. For testing, specimens of 2080 mm in size with transverse welds with two drilled holes were made from the material under study. polished and assembled into cassettes using nickel alloy rods. For the first time, comparative data on the corrosion state of structural materials during evaporation of electrolytic slits obtained by diaphragm electrolysis and electrolysis using a mercury cathode were obtained. The results of corrosion studies are quite well corrected with the experience of operating nickel pipes at the first stage of alkali concentration. The electrochemical heterogeneity of welded joints of alloys 33 and 201 was evaluated. The conducted studies of the corrosion resistance of alloys 201 and 33 under conditions of evaporation of NaOH obtained by mercury electrolysis confirmed the high corrosion resistance of nickel alloy 201 at the main stages of alkali concentration. The research results can be used as recommendations for the development of structural materials.

The influence of a coaxial dielectric rod on eigenvalues, ohmic losses, transverse field structure, and beam-wave coupling coefficients is investigated for TE modes of a gyrotron cavity. It is shown that such dielectric insert, when made from a moderate-loss material, results in strong attenuation of all cavity modes, with the exception of those having caustic radii much larger than the insert radius. It is proposed to employ such dielectric loading for selective suppression of competing modes in cavities of second-harmonic gyrotrons. The high performance and flexibility of the proposed method of mode discrimination are demonstrated for the example of the cavity of the high-power 0.39-GHz second-harmonic gyrotron developed at the University of Fukui. In addition, some fascinating capabilities enabled by coaxial inserts made of ultralow-loss dielectrics are discussed.

The focal surface of a generic space curve in Euclidean $ 3 $-space is a classical subject which is a two dimensional caustic and has Lagrangian singularities. In this paper, we define the first de Sitter focal surface and the second de Sitter focal surface of de Sitter spacelike curve and consider their singular points as an application of the theory of caustics and Legendrian dualities. The main results state that de Sitter focal surfaces can be seen as two dimensional caustics which have Lagrangian singularities. To characterize these singularities, a useful new geometric invariant $ \rho(s) $ is discovered and two dual relationships between focal surfaces and spacelike curve are given. Three examples are used to demonstrate the main results.

The caustic structure of the electromagnetic field is mathematically modeled, when it appears near the ground surface during the decimeter radio wave propagation in the ionospheric plasma. The caustic structures of the fields of the ordinary and extraordinary waves are compared. The influence of the extraordinary wave on the amplitude structure of the ordinary wave field is also estimated in the vicinity of the caustic. The wave fields calculated with the help of the caustic approximation and with the help of the irregular ray approximation are compared. It is suggested to estimate the maximum value of the field amplitude in the vicinity of the caustic on the basis of the ray approximation.

A heterogeneous spent soda effluent generated from Tunisian petroleum refineries has been filtrated and separated in four solid fractions with a particle diameter of 160 to 100, 100 to 40, 40 to 16 and 16 to 10 µm and the fifth one with diameters 2S/Ag electrode studies of the filtrate, show that the whole of the separated fractions contain Na2S, NaHS, C2H5SNa, Na2S2O3, Na2SO3 and methyl, ethyl and propyl mercaptans.

The propagation of wave packets of quantum particles through porous structures in thin semi-transparent films is studied. Numerical solution of the nonstationary Schrodinger equation is used in two-dimensional (for slits) and three-dimensional (round holes) cases. The transmission coefficient of quantum particles is compared with that of classical particles with the same density distribution. The vortex motion of the flux density having a hydrodynamic analog is studied. A variant of the “quantum caustic” is considered upon scattering of the particle wave packet at an obstacle.

Attempt has been made to assess the cotton/modal (60:40) blended woven fabric properties after mercerization with caustic lye of different strengths. Cotton/Modal (60:40) fabric was subjected to bulk mercerization process and subsequently dyed with reactive dyes. The colour strength, fastness properties (washing, staining and rubbing etc.), tensile and tear strength and shrinkage were characterized. The results of this study indicate that cotton/modal blended fabric that was considered in this study can be processed under similar conditions as those that are maintained for cotton fabrics generally and that the aforementioned properties are improved generally.

A paradoxical decrease in the generation threshold of high Stokes and anti-Stokes components of stimulated Brillouin scattering in water has been detected for the first time to our knowledge upon the displacement of the caustic of a focused laser beam from the bulk of water to air. The mechanism of generation of components caused by the four-wave mixing on counterpropagating beams when the water surface serves as the mirror of an induced cavity of a stimulated Brillouin laser is discussed. An upper bound R ≪ 0.02 has been obtained for the reflection coefficient R of distributed feedback at stimulated Brillouin scattering in water.

This article reviews the historical uses of and current research into ion exchange for the removal of cesium from defense-related nuclear waste streams. Emphasis is placed on key attributes of the ...

Sulfur compounds in bitumen-derived gas oil undergo selective oxidation using a titanium-derived catalyst resulting in the formation of sulfones and sulfoxide species. Using caustic solution, the s...

In drilling fluid program, selecting the drilling fluid that will reduce the lost time is the first objective, and will be economical regardless of its cost. The amount and type of solids in drilling fluid is the primary control of the rheological and filtration properties. Palygorskite clay (attapulgite) is an active solid that has the ability to reactive with its environment and form a gel structure within a fluid and due to its stability in the presence of brines and electrolytes this type of clay is preferred for use. The aim of this study is to improve properties of Iraqi palygorskite (PAL) by adding different chemical additives such as caustic soda NaOH and soda ash Na2CO3 with a different concentration in both fresh and salt water-based drilling fluid to satisfy the API specification and to compete with imported palygorskite. The palygorskite claystone of Late Cretaceous age is present in the Western Desert of Iraq within the Digma Formation. In this study, two areas in Western Desert palygorskite were obtained, Bahr Al-Najaf and Trefawi. The results of rheological properties showed that the performance of Bahr Al-Najaf PAL was more affected by caustic soda than Trefawi PAL. In contrast, Trefawi PAL performance was more affected with low concentrations of soda ash than Bahr Al-Najaf PAL in both fresh and salt water-based drilling fluid. Also, these additives lead to improve the value of pH in both fresh and salt drilling fluid that increases the ability of clay to be more dispersed in drilling fluid. Besides that, enhancement of drilling fluid prepared with Iraqi palygorskite stability to 85 and 80 in fresh and saltwater, respectively, was observed with soda ash additions.

This investigation concerns the synthesis as well as structural and morphological characterizations of pure and Ce-doped ZnO nanorods. The samples were synthesized by simple low-temperature hydrothermal process using respectively NaOH and KOH as caustic bases. The as-synthesized nanorods were characterized in terms of their morphological, structural, compositional and vibrational properties. The sizes of the rods were found to be 1.5 μm to 2 μm in length and 250 nm to 300 nm in diameter. The presence of Ce ions in ZnO (NaOH) favored the agglomeration of the rods to form flower-like nanostructures. EDAX measurements showed Zn rich materials with high oxygen vacancy concentration. XRD results indicated that the synthesized ZnO nanorods possess a pure wurtzite structure with good crystallinity. It has also been found that Ce doping deteriorates the crystalline quality of ZnO (NaOH) and improves that of ZnO (KOH). The insignificant intensities observed in FT-IR signals confirm that the synthesized nanorods are of high purity. The Raman spectroscopy studies showed that Ce ions shift the vibrational modes towards lower frequencies. The peaks related to E2 (high) mode in ZnO (KOH) are relatively intense compared to those of ZnO (NaOH). The peaks are found to be shifted and asymmetrically broadened due to anharmonic effects originating from quantum-phonon-effect confinement.

Stochastic progressive photon mapping (SPPM) is one of the important global illumination methods in computer graphics. It can simulate caustics and specular-diffuse-specular lighting effects efficiently. However, as a biased method, it always suffers from both bias and variance with limited iterations, and the bias and the variance bring multi-scale noises into SPPM renderings. Recent learning-based methods have shown great advantages on denoising unbiased Monte Carlo (MC) methods, but have not been leveraged for biased ones. In this paper, we present the first learning-based method specially designed for denoising-biased SPPM renderings. Firstly, to avoid conflicting denoising constraints, the radiance of final images is decomposed into two components: caustic and global. These two components are then denoised separately via a two-network framework. In each network, we employ a novel multi-residual block with two sizes of filters, which significantly improves the model’s capabilities, and makes it more suitable for multi-scale noises on both low-frequency and high-frequency areas. We also present a series of photon-related auxiliary features, to better handle noises while preserving illumination details, especially caustics. Compared with other state-of-the-art learning-based denoising methods that we apply to this problem, our method shows a higher denoising quality, which could efficiently denoise multi-scale noises while keeping sharp illuminations.

Ingestion of Caustic Substances Acids and alkalis can cause tissue damage on contact. Accidental and intentional ingestions of caustic materials in adults and children are a worldwide health issue....

For a family of parallel incoming light rays, we consider the problem of finding a reflecting curve Γ that has as its caustic a given curve γ. First, a geometric string construction for Γ is presen...

Introduction:Accidental ingestion of cleaning substances poses a risk to children all over the world and in our country. In this study, we aimed to investigate the causes of this condition and the clinical problems caused by such serious consequences.Methods:This study was designed as an observational, descriptive, retrospective study. The data were obtained from the hospital electronic medical records. In addition to the demographics, the type of poisoning, presenting complaints, diagnostic tests, medications, treatments and outcomes (results of esophagoscopy and follow-up) were also investigated. The cases were divided into two groups: patients who underwent esophagoscopy and were kept under observation and those kept under observation without esophagoscopy. Patients who underwent esophagoscopy were further divided into two groups as ‘histopathological examination with normal findings ' and ‘histopathological examination with abnormal findings. Hemogram, biochemical parameters and C-reactive protein levels were recorded. The cases with missing or inaccessible data were excluded from the study. The study was approved by the local ethics committee. The SPSS 22.0 program was used for the analysis of the data.Results:Four thousand three hundred forty five had a diagnosis of poisoning and 295 were exposed to corrosive substances. The most common poisoning agent was bleach (23.7%). Of the patients, 132 (57.9%) underwent only clinical follow-up and 96 (42.1%) underwent esophagoscopy with clinical follow-up. The occurrence rate of esophageal strictures was significantly higher in patients ingesting degreasers (p

Using approximate analytical calculations based on the WKB and adiabatic approximations for the mode representation of the field, as well as numerical simulation based on the theory of adiabatic modes, geometric acoustic approximation, and the parabolic equation method, the patterns of the formation and propagation of caustic and weakly diverging acoustic beams in a horizontally inhomogeneous refractive oceanic waveguide are studied. The horizontal distance regions are determined at which the dependences of the acoustic field intensity on the horizontal distance typical of caustic and weakly diverging beams are retained. The study considers the processes involved in reformation of caustic and weakly diverging beams in an oceanic waveguide with increasing water layer depth and constant sound speed profile, which near the source characterized an underwater sound channel open toward the bottom. The conditions are formulated for an effectively matched transition of shallow-water waveguide modes refracted in the thermocline and interacting with the bottom to purely refracted modes of the underwater sound channel in a relatively deep water part of the oceanic waveguide.

Aim of the Study: Esophageal dilatations are commonly performed in pediatric patients who have undergone an esophageal atresia/tracheoesophageal fistula (EA/TEF) repair or following caustic injury. We sought to compare the practice of esophageal dilatation across different specialties. Methods: We analyzed all patients who had an esophageal dilatation at our center between April 2014 and December 2018. Patients were identified via prospectively maintained databases and clinical coding records. Patients had a combination of dilatations under each specialty: interventional radiology (IR), surgery, and gastroenterology. Results: Thirty-five individual patients underwent 226 dilatations, median dilatations per patient was 3 (1–40). The median age at first dilatation was 18 months (1–194 months). Sixty-eight percent of patients had a previous EA/TEF repair. IR performed 59% of dilatations, surgeons 26%, and 15% by gastroenterologists. Surgeons more frequently were performing initial dilatations (P

peer-reviewed Traditionally, symmetric accelerating beam (SAB) generation requires bulky optical components, which hinder the miniaturization of optical systems. Recently, metasurfaces, which are composed of sub-wavelength features, have provided a captivating boulevard for the realization of ultra-thin and flat optical devices. Therefore, for the first time, we design and simulate all-dielectric metasurfaces based on an optical caustic approach to generate highly efficient SABs by tailoring the phase of an incident wave. The designed metasurface utilizes spatial distribution of optimized Nb2O5 nano-rods on SiO2 substrate to perform the phase modulation. In contrast with conventional accelerating beams, the generated SABs can follow any predefined propagation trajectory with unique features, such as symmetric intensity profile, autofocusing, and thin needle-like structure in their intensity profile. In addition to this, these beams have also shown the ability to avoid obstacles, placed in the direction of propagation of main lobes. We believe that these beams can be useful in applications, including Raman spectroscopy and fluorescent imaging, and multiparticle manipulation.

In this paper, it is proven that for any optical system with a circular exit pupil and wavefronts affected by any aberrations, the borders of all leaving rays are caustic surfaces and/or marginal rays. Several examples are shown for wavefronts affected by linear combinations of Zernike aberrations.

A new, to the best of our knowledge, method for designing a thick-lens achromatic doublet based on the concept of a caustic surface to correct both third- and fifth-order spherical aberration is presented. We consider two different wavelengths brought into coincidence at the back focal length instead of the effective focal length as it is usually done, to calculate the radii of curvature assuming predefined values for axial thicknesses and their indices of refraction for both lenses. Alternatively, we apply Taylor’s series around the optical axis, and to vanish the approximate caustic surface, we obtain the values for the conic constants, which reduce at third- and fifth-order spherical aberration. Two designs for cemented doublets are provided assuming that the lenses are cemented. Finally, we propose a method to qualitatively test doublet lenses by using null screens, considering to place the detection plane at arbitrary positions.

Two studies explored how the triarchic dimensions of psychopathy predicted relationship outcomes in nonclinical samples. In Study 1, using a predominantly student sample ( N = 100, 24% men, 76% women), results revealed significant negative associations between meanness and Sternberg’s (1997) components of love (intimacy, passion, and commitment). In Study 2, using a more gender-balanced online community sample ( N = 125, 53% men, 47% women), we replicated results from Study 1 and found additional negative associations between self-reported physical aggression, psychological aggression and love in intimate relationships. Further, multivariate analyses revealed that deficits in love explained incremental variance in intimate partner aggression, over and above the triarchic constructs of meanness and disinhibition. Implications for how dimensions of psychopathy manifest in close intimate relationships are discussed.

One-part or “just add water” alkali activated materials (AAMs) have attracted a lot of attention thanks to the use of solid alkaline activators that makes these materials more suitable to commercialization compared to conventional AAMs (two-part). This is mainly because large quantities of caustic solutions should be handled for producing conventional AAMs. So, one-part AAMs have a great potential for in-situ applications. However, heat curing (